Bart Chilton will stick around the Commodity Futures Trading Commission long enough to vote on the Volcker rule tomorrow.

The CFTC and three other federal regulators are set to vote on the proposal, which will bar banks from proprietary trading and strictly limit their alternative investments activities, tomorrow, with the Securities and Exchange Commission soon to follow.

The rule expected to be approved tomorrow is significantly tougher than drafts from just a few weeks ago, with tougher restrictions on bank hedging and a requirement that CEOs affirm that their bank is not violating the prohibition on prop. trading. That could be key—when Chilton announced his plans to leave the CFTC last month, he indicated that he would not vote for the Volcker rule in its weaker form.

It is unclear if the changes will have mollified Chilton. If they have not, the CFTC will be unable to pass the rule, as Chilton's "no" vote would leave the regulator deadlocked.

Chilton said he decided to stay on at the urging of lawmakers.

"The timing will allow me to vote on the Volcker rule," he said. "As long as I'm a commissioner and not conflicted or recused from an issue, I intend to fulfill the responsibilities of the office."

U.S. Treasury Secretary Jacob Lew has pushed the five cooperating regulators to approve the rule, which was mandated by 2010's Dodd-Frank financial regulation law. On Thursday, he said that the rule "prohibits risky proprietary trading while protecting economically essential activities like market-making."

Even if the rule is approved, it is unlikely to come into force until 2015.

From the current issue of

MODERN TRADER explores the effect of a potential trade war on U.S. equity markets. Will it end the bull run or will low interest rates allow U.S. equities to maintain its momentum? Read on. We also attempt to identify the key drivers of active equity hedge funds.